Abstract: A method useful for forming a composite part having regions in which fibers align with the principle stress vectors as well as regions having a randomized fiber alignment. To form the randomized fiber alignment, a preform cavity is formed in a preform arrangement, and the preform arrangement is molded in accordance with compression molding protocols to form a part.

Abstract: A method for rapid heat cycle compression molding comprises placing an assemblage of feed constituents in a mold, placing the mold between two hot platens of a hot press, heating the mold by pressing the two hot platens against the mold, placing the mold between two cold platens of a cold press, cooling the mold by pressing the two cold platens against the mold, and ejecting the part from the mold.

Abstract: A hybrid preform comprises a bundle of unidirectionally aligned fibers, and at least one partial cut that extends part of the way, but not all of the way, through a transverse cross section of the bundle of fibers at least one location along the length of the bundle.

Abstract: A fiber-composite part having one or more electronic components that are located in arbitrary regions of the internal volume of the part are fabricated using a preform charge. The preform charge has a structure that corresponds to that of the mold cavity in which the part is being formed. By incorporating the electronic components in the preform charge, such components are then precisely located, spatially oriented, and constrained, and such location and orientation is maintained during molding to produce a part with the electronic components in the desired locations and orientations within its internal volume.

Abstract: An apparatus for molding a part includes a plunger cavity, a plunger, and a mold cavity, wherein the plunger is oriented out-of-plane with respect to a major surface of the mold cavity, and first and second vents couples to respective first and second portions of the mold cavity. In a method, resin and fiber are forced into the mold cavity from a plunger cavity, and at least some of the fibers and resin are preferentially flowed to certain region in the mold cavity via the use of vents.

Abstract: A preform-charge fixture creates a preform charge, which is a partially consolidated assemblage of preforms that can be efficiently transferred to a mold to create a finished part in a molding process, such as compression molding. In the illustrative embodiment, the preform-charge fixture includes peripheral cleats that are movable towards a central cleat to create a small gap therebetween that receives and constrains preforms in a desired position. The fixture also includes clamps, which are operable to engage an uppermost layer of preforms in the gap and apply a slight amount of downward pressure thereto to assure that the preforms are properly seated. The fixture also accommodates an energy source that heats the preforms so that, in conjunction with downforce applied by the clamps and/or gravity, the preforms can be tacked together, forming the preform charge.

Abstract: Some embodiments of a compression mold for forming a rib-and-sheet part includes a mold cavity and a mold insert. A sheet is placed in the mold cavity, and the mold insert is placed on the sheet. A preform assemblage is placed in a gap that is formed between the mold insert and the wall of the mold cavity. A mold core is biased above the preform assemblage, prior to molding operations, via a compression spring.

Abstract: Rib-and-sheet structures include a rib comprising continuous, aligned fibers. The rib is fabricated via compression molding from continuous, aligned fiber, thereby providing an aligned, continuously reinforced rib. In one embodiment, rib-and-sheet structures are produced in a two-step compression-molding process, wherein a near net-shape rib is molded, in a first mold, from fiber-bundle based preforms, and then a rib-and-sheet part is molded by placing, in a second mold, the rib with either: (i) a preformed sheet, (ii) plies that form a laminate/sheet or (iii) chopped fibers that form a sheet during the molding process. In another embodiment, rib-and-sheet structures are fabricated in a one-step compression-molding process, wherein fiber-bundle-based preforms and (i) a preformed sheet, (ii) plies that form a laminate/sheet, or (iii) chopped fibers are combined in a single mold and molded in a single step.

Abstract: A hybrid preform comprises a bundle of unidirectionally aligned fibers, and at least one partial cut that extends part of the way, but not all of the way, through a transverse cross section of the bundle of fibers at least one location along the length of the bundle.

Abstract: An apparatus for molding a part includes a plunger cavity, a plunger, and a mold cavity, wherein the plunger is oriented out-of-plane with respect to a major surface of the mold cavity, and first and second vents couples to respective first and second portions of the mold cavity. In a method, resin and fiber are forced into the mold cavity from a plunger cavity, and at least some of the fibers and resin are preferentially flowed to certain region in the mold cavity via the use of vents.

Abstract: Method and apparatus for splaying fibers for the forming preform charges for the production of composite discs, and for the production of composite disc, wherein rotary compaction is applied to an appropriately arranged assemblage of preforms.

Abstract: A method and apparatus for the continuous fabrication of fiber-bundle-based and composite-tape based preforms and preform charges includes a mandrel about which a constituent material, which is maintained under tension, is wound. The tension is insufficient to fully consolidate the wound material.

Abstract: An apparatus for molding a part includes a plunger cavity, a plunger, and a mold cavity, wherein the plunger is oriented out-of-plane with respect to a major surface of the mold cavity, and first and second vents couples to respective first and second portions of the mold cavity. In a method, resin and fiber are forced into the mold cavity from a plunger cavity, and at least some of the fibers and resin are preferentially flowed to certain region in the mold cavity via the use of vents.

Abstract: A system and methods are disclosed for producing compression-molded components having one or more desired characteristics with respect to one or more objectives. In accordance with one embodiment, a parameter space comprising a set of values of a parameter is defined, where the parameter corresponds to a property of fiber bundles, and where the set of values represents all possible values of the parameter in the parameter space. The parameter space is narrowed, and a statistical model is generated based on a sampling of the narrowed parameter space. A value of the parameter is selected based on the statistical model, and a bundle of fibers conforming to the selected value is produced. A component comprising the bundle of fibers is then manufactured using a compression-molding process.

Abstract: A compression molding method for creating fine, features having desired fiber-alignment patterns involves creating a pressure gradient in a mold cavity during the soak phase of the compression-molding process. In the illustrative embodiment, the gradient is created by movement of a structure, and results in a flow of nearby fiber and melted resin. This alters local, preexisting, non-random fiber alignments. The process imparts geometries to a part (the bulging features) that are not otherwise present on the mold surface.

Abstract: A method for forming fiber-reinforced composite parts via compression molding, particularly useful for forming parts that include off-axis, out-of-plane, or small, intricate features. In accordance with the method, non-flowing continuous fiber bundles and flowing continuous fiber bundles are placed in a mold, wherein the flowing continuous fiber bundles are disposed proximal to a minor feature. The non-flowing bundle has a length about equal to the length of a major feature of the mold. The flowing bundle has a length that is somewhat longer than the length of the minor feature. Under heat and pressure, resin softens and fibers from the flowing continuous fiber bundles flow into the minor feature.

Abstract: A method for designing fiber-composite parts in which part performance and manufacturing efficiency can be traded-off against one another to provide an “optimized” design for a desired use case. In some embodiments, the method involves generating an idealized fiber map, wherein the orientation of fibers throughout the prospective part align with the anticipated load conditions throughout the part, and then modifying the idealized fiber map by various fabrication constraints to generate a process-compensated preform map.

Abstract: Some embodiments of a compression mold for forming a rib-and-sheet part includes a mold cavity and a mold insert. A sheet is placed in the mold cavity, and the mold insert is placed on the sheet. A preform assemblage is placed in a gap that is formed between the mold insert and the wall of the mold cavity. A mold core is biased above the preform assemblage, prior to molding operations, via a compression spring.

Abstract: A multi-part compression mold for forming a complex part having a desired fiber alignment, and methods therefor, are disclosed. The multi-part mold comprises at least three sections. Specific arrangements of fiber-bundle-based preforms are introduced to more than one of the mold sections of the multi-part mold, and subjected to compression molding. The arrangements of preforms, in conjunction with the multi-part mold, result in a complex part having fibers that substantially align with anticipated principle stress vectors that arise in the complex part, when in use.

Abstract: A method useful for forming a composite part having regions in which fibers align with the principle stress vectors as well as regions having a randomized fiber alignment. To form the randomized fiber alignment, a preform cavity is formed in a preform arrangement, and the preform arrangement is molded in accordance with compression molding protocols to form a part.